Mogadishu , Somalia -LRB- CNN -RRB- -- Al-Shabaab militants killed at least 12 people Tuesday in a car bombing and assault on a police station shared by African Union peacekeepers in a key Somali commercial hub , authorities said .

At least four of the Islamist attackers also were killed as Somali police and AU troops responded to the assault on the police station in Beledweyne , about 200 miles north of the Somali capital of Mogadishu , said Abdi Farah Laqanyo , governor of the Hiran region .

The attack is the latest on Somali and AU forces by Al-Shabaab , a group that is fighting the government in hopes of turning Somalia into a fundamentalist Islamic state .

A car packed with explosives was driven into the station 's gate and burst `` into a huge ball of flames '' about 11 a.m. , Laqanyo said .

Attackers then entered the police compound and exchanged fire with police and AU forces , authorities said . The station is a base for Djiboutian troops serving as peacekeepers for the African Union Mission in Somalia , known as AMISOM , which supports Somali forces in cracking down on Al-Shabaab .

The attack killed at least 10 defenders -- six Somali policemen and four Djiboutian soldiers with AMISOM -- said Col. Abdilkadir Osman , a police officer in the town . Two civilians also were killed , authorities said .

A spokesman for Al-Shabaab 's military operations , Sheikh Abdiaziz Abu Musab , said the group carried out the attack . Abu Musab claimed the attack killed 18 AMISOM troops and 23 Somali forces , though CNN could not independently verify that count .

A witness who was 200 meters from the site said the attackers used assault rifles , machine guns and rocket-propelled grenades after the car bombing . The witness , speaking on condition of anonymity , said a plume of black smoke rose from the police station .

Tuesday 's fighting comes less than a month after a suicide attack claimed by Al-Shabaab killed 16 people at a cafe in Beledweyne .

Somali President Hassan Sheikh Mohamud said Tuesday he was sending condolences to the victims of what he said was a `` stupid attack . ''

`` I say this was a stupid attack because our enemies need to understand that these attacks do nothing to advance their cause , however misguided , '' Mohamud said . `` We are making great progress while our enemies are on the back foot and reduced to sporadic and self-defeating attacks with no regard to life . ''

Beledweyne is the capital of the Hiran region . Situated near the Ethiopian border , it is a commercial hub linking southern and northern Somalia .

Though Al-Shabaab is fighting the Somali government , it has launched attacks in other countries as well , and it has a relationship with al Qaeda that goes back several years . Al-Shabaab claimed responsibility for September 's four-day siege at the Westgate Mall in Nairobi , Kenya , where at dozens of people were killed .

The U.S. government designated Al-Shabaab as a foreign terrorist organization in March 2008 .

Journalist Omar Nor reported from Mogadishu . CNN 's Jason Hanna wrote from Atlanta . CNN 's Nana Karikari-apau contributed to this report .

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Islamist group Al-Shabaab claims responsibility

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Car bomb explodes at gate of police station in Beledweyne , Somalia

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Al-Shabaab fighters then enter compound , exchange fire with police and AU troops

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Six Somali policemen and four Djiboutian peacekeepers among the dead , police say